Lloyd



UNITED STATES PATENT OFFICE.

MARCEL PERREUR-LLOYD, OF PARIS, FRANCE, ASSIGNOR TO THE ELEC- TRICAL COPPER COMPANY, LIMITED, OF LONDON, ENGLAND.

ELECTROLYTIC APPARATUS AND PROCESS OF TREATING IMPREGNATORS THEREFOR.

SPECIFICATION forming part of Letters Patent No. 626,033, dated May 30, 1899.

Application filed July 9, 1898. Serial No. 685,573. (No modelJ To all whom, it may concern.- mence to soften when the electrolytic bath Be it known that I, MARCEL PERREUR- reaches a temperature of about 86 Fahren- LLOYD, a citizen ofthe French Republic, reheit (or 30 centigrade) and even begin to siding at Paris, in the Department of the disintegrate or dissolve in the bath. Under Seine, France, have invented certain newand such a condition of temperature the con- 55 useful Improvements in Electrolytic Appatrolling action of the impregnators is comratus and Process of Treating Impregnators pletely changed, and instead of temporarily Therefor, of which the following is a full, coating or coveringslightly the asperities and clear, and exact description. prominences parts of the impregnators may :0 In the specification of Letters Patent No. permanently adhere to and little by little 60 560,533 granted to me and issued on-the 19th become imprisoned in the metallic deposit. day of May, A. D. 1896, relating to the elec- When the metal is subsequently annealed, trodeposition of copper and other metals on thisimprisoned matter by its combustion prorotary cathodes there are described certain duces gases under pressure which render the p organic membranes or materials which are metal porous and short. To obviate this de- 65 arrangedinlight contact with rotarycathodes feet and inconvenience is the object of my upon which the metal is deposited for the purinvention, in carrying out which I treat the pose of insuringa smooth, uniform,and homoimpregnators in such a manner and by such geneous product. These organic membranes, means as to render them practically insoluble 20 which have been and are hereinafter called and disintegratable under ordinary working 70 impregnators,act by momentarily covering conditions. This may be effected, for exor coating and electrically or physically insuample, by means of a solution of potassium lating temporary asperities or prominences on bichromate with subsequent drying and sothe deposit and thus prevent or retard depolarization; but this method may in some sition of the metal thereon. Meanwhile the cases be attended with the inconvenience that 7 molecules of metal are normally deposited unless sufficient care be taken it may introaround the asperities or prominences, and duce a foreign salt into the electrolyte. For these latter thus become level with the genthis reason I prefer to treat the impregnators eral surface of the cathode. The coating or with a solution of formic aldehyde, which 0 covering derived from the impregnators is aldehyde, being gaseous, may be entirely 8o gradually removed by the motion of the catheliminated from the impregnators after it has ode in the electrolyte and in contact with acted'thereon and before they are putinto use. the impregnators and is also gradually re- According to my present invention, which newed, but only so long as any prominence or is an apparatus and a process, the impregna- 5 asperity exists. By this use of the impregtors are thoroughly impregnated with the so- 85 nators I obtain deposits having remarkably lution of formic aldehyde, after which they excellent physical and mechanical qualities may be copiously washed in water to remove and which are also produced much more the aldehyde, or this substance may be neurapidly than by preexisting methods. For tralized or rendered inoperative or inert after 40 example, a sheet of copper one twenty-fifth it has acted on the impregnators-as, for ex- 0 of an inch thick maybe obtained in about ten ample, by means of acetic acid, which it has hours working. This rapidity of deposit is been found will accomplish this end. The an economical advantage, but it has also the object of this washing orneutralization is that disadvantage that owing to the heavy density the action of the aldehyde 'may not be con- 5 of the current employed 'a rapid heating of tinned further than is necessary and that 5 the electrolytic bath ensues and the increase none of it may beintroduced into the electroof temperature therein may easily suflice to lyte. The solution may be used in various bring about the softening or solution of some strengths; but it is generallyemployed within of the albuminous or gelatinous constituents the limits of ten per cent. and forty per cent.,

oftheimpregnators. Theseconstituents comaccording to the nature of the material of too which the impregnators are composed, to the time within which the insolubilization must be eifected, and other minor considerations, such as the temperature of the solution. For example, if a forty-pcr-cent. solution of formic aldehyde be used the impregnators, if of the nature of parchment, may be soaked in the cold solution for about one and a half hours, he removed therefrom and dried, and be then soaked in clean water for fifteen hours or until wanted. Soaking for a longer time is not prejudicial. Again, if similar impregnators are treated with a ten-per-cent. solution of formic aldehyde they may he suffered to remain in the cold solution for fifteen hours and be thereafter treated as hereinbefore described with respect to the forty-per-cent. solution. If time cannot be spared for the soaking in water, the impregnators, after removal from the formic-aldehyde solution, may be heated for a short time in a bath of commercial acetic acid and be thereafterthoroughly washed in clean water.

like manner the subsequent treatment may also be varied.

IVhen the impregnators, rendered more or less insoluble, as hereinbefore described, are employed in connection with rotary cathodes in the electrodeposition of copper or other metals, the metal maybe deposited with equal facility in a hot or in a cold bath, and the impregnators are found to be much more durable.

What I claim as my invention, and desire to secure by Letters Patent, is

1. In an electrolytic apparatus, the combination of an anode, a rotary cathode, an impregnator of animal-membranes having its albuminous and gelatinous constituents com bined with formaldehyde and means for holding the impregnator in light contact with the cathode.

2. The process of treating impregnators for use in electrolytic apparatus, which consists in thoroughly impregnating the impregnator with a solution of formic aldehyde and sub sequently rendering the aldehyde inert or inoperative by treating the imprcgnator in a bath of commercial acetic acid.

In witness whereof Isubscribc my signature in presence of two witnesses.

MARCEL PERREUR-LLOYD.

\Vitnesses:

Goncns RENERT, EDMUND JOHN TURNER. 

